My laboratory investigations are focused on identifying genes that control the growth and differentiation of breast cancer cells. We are utilizing several human breast cancer cell lines that can be induced to differentiate in vitro in response to a variety of hormones, chemical agents, and polypeptide growth factors. Several approaches are being undertaken to identify the critical genes that control the growth and differentiation of these cells. WE are investigating the role of genes known to be important in regulating growth and differentiation in other systems. We are also searching for new members of gene families whose members are known to play a role in controlling cell growth and differentiation. In addition, we are identifying new genes involved in cell growth and differentiation using several differential cloning techniques. As potential target genes are identified, their function will be studied to uncover their role in the growth and differentiation of breast cancer cells.